1. Diarrhea is defined as having more than 3 loose or liquid stools per day. It can be acute (lasting less than 2 weeks) or chronic (lasting more than 4 weeks). 2. Acute diarrhea is often infectious and can be classified as watery, bloody, or dysentery. Evaluation is needed if bloody, associated with fever or infection, or not resolving. Chronic diarrhea often has non-infectious causes like IBS. 3. History and symptoms help determine the cause and guide testing/treatment. Infectious acute diarrhea may require antibiotics while watery diarrhea often resolves on its own with rehydration. Chronic diarrhea distinguishes organic from functional causes.

1. APPROACH to
DIARRHEA
DR.Bilal Natiq Nuaman,MD
C.A.B.M. , F.I.B.M.S. , D.I.M.
Assistant Professor at Al-Iraqia Medical College
2019-2020

2. Normal bowel motions :
3stools by 1day
(> 3 STOOLS /DAY DIARRHEA)
1stool by 3days
(1 STOOL / >3DAYS CONSTIPATION )

3. DIARRHEA
Diarrheal diseases represent one of the
five leading causes of death worldwide.
Diarrhea is both a symptom and a sign.
As a symptom, diarrhea is most often
reported as a decrease in stool
consistency and an increase in stool
volume.
As a sign, diarrhea is defined as a stool
weight (i.e., water content) that exceeds
200 g in 24 hours.

4. It is important to relate this symptom to
the patient’s history:
• Elderly (cancer, polyps, diverticular
disease, ischaemic colitis).
• Young/thin female (laxative abuse).
• Travel/local conditions (infection, post-
infectious irritable bowel syndrome).
• Previous episodes (inflammatory bowel
disease,irritable bowel syndrome).
• Medications (recent broad-spectrum
NSAIDs, proton-pump inhibitors,
fluoxetine, immunosuppressants, etc.).

5. • Recent-onset diabetes mellitus (pancreatic
cancer with insufficiency).
• Systemic features (inflammatory bowel
disease, ankylosing spondylitis).
• Previous surgery (vagotomy, Polya
gastrectomy, cholecystectomy, terminal
ileal resection).
• Family history (inflammatory bowel
disease, gluten enteropathy, colorectal
cancer/polyposis, multiple endocrine
neoplasia).
• Gluten enteropathy with recent
deterioration (lymphoma).

6. classifications of diarrhea
Acute diarrhea vs.
Chronic diarrhea

7. ACUTE DIARRHEA
Diarrhea lasting < 2 weeks
• Acute diarrhea is an extremely common
presenting problem, and mostly due to
infectious causes.
• It is self-limited, No evaluation is necessary
unless the stools are bloody and fever or
infection is suspected (e.g., from travel
history or a common source outbreak). If
these conditions exist, do not treat with
antimotility agents.
• Begin the evaluation with stool studies for
bacterial pathogens, ova, and parasites and
proctosigmoidoscopy.

8. Acute diarrhea categorized into 3
categories: noninfectious,
gastroenteritis, and infectious
colitis.
A-Noninfectious diarrhea is
recognized by the lack of
constitutional symptoms.

9. Noninfectious diarrhea, causes:
1. Medications and other ingestible
substances (some with osmotic
effect)
a. Sorbitol (gum) b. Mannitol
c. Fructose (fruits, soft drinks)
d. Fiber (bran, fruits, vegetables)
e. Lactulose
2. Magnesium-containing medications
a. Nutritional supplements
b. Antacids c. Laxatives
• Antidepressants

10. 3. Malabsorption
a. Lactose intolerance
b. Pancreatitis
4. Medications causing diarrhea
through nonosmotic means
a. Metformin
b. Antibiotics
c. Colchicine
d. Digoxin
e. Selective serotonin reuptake

11. B-Infectious diarrhea that
presents with large volume
(often watery) stool,
constitutional symptoms,
nausea and vomiting, and often
abdominal cramps can be
categorized as gastroenteritis.

12. Infectious diarrhea: gastroenteritis,
causes:
1. Viral (most common)
2. Bacterial
a. Vibrio cholera
b. Escherichia coli
c. Shigella species
d. Salmonella species
3. Toxin-mediated
a. Staphylococcus aureus
b. Clostridium perfringens
c. Bacillus cereus

13. 3-Infectious colitis presents with
fever, tenesmus, and dysentery
(stools with blood and mucus).
• Infectious diarrhea:
inflammatory colitis, causes
1. Shigella species
2. E coli
3. Campylobacter species
4. Salmonella species
5. Clostridium difficile

14. Acute diarrhea
Classified into:
1- watery diarrhea Vs. bloody
diarrhea
2-Infectious diarrhea Vs. non
infectious diarrhea

17. Food poisoning
• Symptoms that begin within six hours
suggest ingestion of a preformed toxin of
Staphylococcus aureus or Bacillus cereus
• Symptoms that begin at 8 to 16 hours
suggest infection with Clostridium
perfringens
• Symptoms that begin at more than 16 hours
can result from viral or bacterial infection (eg,
E. coli).

18. Infectious acute diarrhea is usually
associated with abdominal colicky pain,
urgency, tenesmus,nausea and
vomiting, watery stools, with or without
blood or mucus.
Systemic symptoms such as fever and
myalgia may be present.
In severe cases of diarrhea, urgency of
defecation and fecal incontinence is a
common event.

19. Tenesmus :
A sensation of incomplete evacuation
often accompanied by abnormally
frequent desire to defecate with
involuntary painful straining , but little
bowel movement.
• Causes of tenesmus
1-inflammatory bowel disease
2-colorecteal cancer
3-amebiasis
4- shigellosis
5-diverticular disease

20. (dysentery)

21. Fecal urgency:
the sudden, almost uncontrollable, need to
defecate.
Fecal incontinence :
complete inability to control the bowel
movements, resulting in the involuntary
passage of stool.

22. History should include recent consumption
of unsanitary food or water (raw or poorly
cooked foods such as eggs, meat, shellfish,
dairy products, fruits and vegetables, or
foods that may have been improperly
handled or stored)
EXCLUDE FOOD POISONING

23. Important features in history of acute diarrhea:
• Stool characteristics-frequency, consistency,
quantity, bloody, mucus-filled , purulent.
• Presence of dysentery—fever, tenesmus ,
blood, mucus, or both;
• Symptoms of dehydration—thirst , lethargy,
postural giddiness, decreased urination; and
• Presence of associated symptoms—nausea,
vomiting, abdominal cramps, and significant
upper or lower gastrointestinal bleeding (coffee
ground hematemesis,melena, hematochezia).

24. • Cholera may present very suddenly
with vomiting and acute watery
diarrhea with a “rice-water” appearance
of stool; but cholera not associated
with frank abdominal pain, tenesmus,
or Fever.
• shigellosis is typically characterized by
acute bloody diarrhea with or without
mucous associated with abdominal
cramps and tenesmus along with fever
and anorexia.

26. Indications for diagnostic evaluation
• Profuse watery diarrhea with signs of hypovolemia
• Passage of many small volume stools containing
blood and mucus
• Bloody diarrhea
• Temperature ≥38.5ºC (101.3ºF)
• Passage of ≥6 unformed stools per 24 hours or a
duration of illness >48 hours
• Severe abdominal pain
• Hospitalized patients or recent use of antibiotics
• Diarrhea in the elderly (≥70 years of age)
• Systemic illness with diarrhea, especially in
pregnant women

27. Complications of acute diarrheal diseases
1-Hypovolemia and electrolyte imbalances
(cholera).
2-Bacteremia (Non typhoidal Salmonella )
3-Hemolytic-uremic syndrome- triad of acute
renal failure, microangiopathic hemolytic
anemia, and thrombocytopenia
(enterohemorrhagic Escherichia coli (EHEC))
4-Guillain-Barré syndrome-ascending
symmetrical paralysis (Campylobacter)
5-Reactive arthritis (formerly Reiter syndrome).
6- Rectal prolapse, toxic megacolon (Shigella)

28. treatment
• Watery diarrhea — Antimicrobial therapy
is not typically indicated for the treatment
of acute watery diarrhea in adults, as most
cases resolve spontaneously. An
important exception is the treatment of
severe cholera (doxycyclin,azithromycin,
ciprofloxacin)
• Bloody diarrhea — adults with bloody
diarrhea should be treated promptly with
an antimicrobial that is effective against
Shigella.(ciprofloxacin)

29. Chronic diarrhea
Diarrhea lasting >4 weeks
• most cases of chronic diarrhea are
noninfectious—IBS being the leading
cause of chronic diarrhea
• Differentiate organic diarrhea from
functional diarrhea.

30. • IBS (Irritable Bowel Syndrome)-
Recurrent abdominal pain associated
with chronic diarrhea and improved
with defecation
• Large volume diarrhea, bloody
stools, nocturnal diarrhea, and
greasy stools are not associated
with IBS and suggest an organic
disease.
• Functional diarrhea — continuous
or recurrent passage of watery
stools without abdominal pain or
discomfort

31. Medical history:
AIDS, diabetes, cirrhosis, sickle cell disease,
cancer, endocrine – thyroid disease.
previous surgery (surgery for peptic ulcer,
cholecystectomy, and ileal resection),
irradiation,

32. Typical features of chronic diarrhea :
• Nocturnal diarrhea—autonomic neuropathy,
e.g. diabetes mellitus;
• Diarrhea alternating with constipation -TB
abdomen, laxative abuse, diverticulosis,
carcinoma of colon;
• Chronic bloody or melanotic stools with
weight loss - IBD, colonic malignancy;
• Pale, bulky, greasy, frothy, foul-smelling
stools, which float in toilet, and associated
with nutritional deficiency, weight loss-
malabsorption syndrome.

33. Chronic diarrhea
classified into:
1-Organic vs. Functional diarrhea
2-Small bowel (right sided) vs.
Colonic diarrhea (left sided)
3-Osmotic vs. Secretory

36. • Osmotic diarrhea small
volume , responds to fasting
• Secretory diarrhea large
volume ,not responds to
fasting